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			<h1>JavaScript <span class="color_h1">类型转换</span></h1>

<hr>
<p>Number() 转换为数字， String() 转换为字符串， Boolean() 转换为布尔值。 </p>
<hr>
<h2>JavaScript 数据类型</h2>
<p>在 JavaScript 中有 6 种不同的数据类型：</p>
<ul>
	<li>string</li>
	<li>number</li>
	<li>boolean</li>
	<li>object</li>
	<li>function</li>
<li>symbol</li>
</ul>
<p>3 种对象类型：</p>
<ul>
	<li>Object</li>
	<li>Date</li>
	<li>Array</li>
</ul>
<p> 2 个不包含任何值的数据类型：</p>
<ul>
	<li>null</li>
	<li>undefined</li>
</ul>
<hr>

<h2>typeof 操作符</h2>
<p>你可以使用 <strong>typeof</strong> 操作符来查看 JavaScript 变量的数据类型。</p>
<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highELE">typeof</span> <span class="highVAL">"John"</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 string <br></span>
<span class="highELE">typeof</span> <span class="highVAL">3.14</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 number<br></span>
<span class="highELE">typeof</span> NaN &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 number<br></span><span class="highELE">typeof</span> <span class="highVAL">false</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 boolean<br></span><span class="highELE">typeof</span> [<span class="highVAL">1</span>,<span class="highVAL">2</span>,<span class="highVAL">3</span>,<span class="highVAL">4</span>]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="highCOM">// 返回 object<br></span>
<span class="highELE">typeof</span> {name:<span class="highVAL">'John'</span>, age:34}&nbsp;
<span class="highCOM">// 返回 object<br></span><span class="highELE">typeof</span> <span class="highELE">new</span> Date()&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 object<br></span><span class="highELE">typeof</span> <span class="highELE">function</span> () {} &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 function<br></span>
<span class="highELE">typeof</span> myCar&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 undefined (如果 myCar 没有声明)<br></span>
<span class="highELE">typeof</span> <span class="highVAL">null</span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回 object
</span></div>
<br>
<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_typeof_all" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<p>请注意：</p>
<ul>
	<li> NaN 的数据类型是 number</li>
	<li> 数组(Array)的数据类型是 object</li>
	<li> 日期(Date)的数据类型为 object</li>
	<li> null 的数据类型是 object</li>
	<li> 未定义变量的数据类型为 undefined</li>
</ul>

<p>如果对象是 JavaScript Array 或 JavaScript Date ，我们就无法通过 <strong>typeof</strong> 来判断他们的类型，因为都是 返回 object。</p>
<hr>

<h2>constructor 属性</h2>
<p> <strong>constructor</strong> 属性返回所有 JavaScript 变量的构造函数。</p>
<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highVAL">"John"</span>.constructor&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回函数 String()&nbsp; { [native code] }<br></span>
(<span class="highVAL">3.14</span>).constructor&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// 返回函数 Number()&nbsp; { [native code] }<br></span>
false.constructor&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<span class="highCOM">// 返回函数 Boolean() { [native code] }<br></span>
[<span class="highVAL">1</span>,<span class="highVAL">2</span>,<span class="highVAL">3</span>,<span class="highVAL">4</span>].constructor&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<span class="highCOM">// 返回函数 Array()&nbsp;&nbsp; { [native code] }<br></span>
{name:<span class="highVAL">'John'</span>, age:34}.constructor&nbsp;
<span class="highCOM">// 返回函数 Object()&nbsp; { [native code] }<br></span>
	<span class="highELE">new</span> Date().constructor&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;
<span class="highCOM">// 返回函数 Date()&nbsp; &nbsp; { [native code] }<br></span>
<span class="highELE">function</span> () {}.constructor &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<span class="highCOM">// 返回函数 Function(){ [native code] }
</span></div>
<br>
<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_constructor_all" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>

<p>
你可以使用 constructor 属性来查看对象是否为数组
(包含字符串 "Array"):</p>

<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highELE">function</span> isArray(myArray) {<br>
&nbsp;&nbsp;&nbsp; <span class="highELE">return</span> myArray.constructor.toString().indexOf(<span class="highVAL">"Array"</span>) &gt; <span class="highVAL">-1</span>;<br>
}
</div>
<br>
	<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_array_isarray" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>

<p>你可以使用 constructor 属性来查看对象是否为日期
(包含字符串 "Date"):</p>

<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highELE">function</span> isDate(myDate) {<br>
&nbsp;&nbsp;&nbsp; <span class="highELE">return</span> myDate.constructor.toString().indexOf(<span class="highVAL">"Date"</span>) &gt; <span class="highVAL">-1</span>;<br>
}
</div>
<br>
	<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_date_isdate" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<br>
<hr>

<h2>JavaScript 类型转换</h2>
<p>JavaScript 变量可以转换为新变量或其他数据类型：</p>
<ul>
	<li>通过使用 JavaScript 函数</li>
	<li>通过 JavaScript 自身自动转换</li>
</ul>
<hr>
<h2>将数字转换为字符串</h2>
<p>全局方法 <strong>String()</strong> 可以将数字转换为字符串。</p>

<p>该方法可用于任何类型的数字，字母，变量，表达式：</p>
<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
	String(x)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="highCOM">// 将变量 x 转换为字符串并返回<br></span>
	String(<span class="highVAL">123</span>)&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <span class="highCOM">// 将数字 123 转换为字符串并返回<br></span>
	String(<span class="highVAL">100</span> + <span class="highVAL">23</span>)&nbsp; <span class="highCOM">// 将数字表达式转换为字符串并返回</span></div>
<br>
	<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_number_string" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<p> Number 方法 <strong>toString()</strong> 也是有同样的效果。</p>

<div class="example">
<h2 class="example">实例</h2>
	<div class="example_code">
x.toString()<br>(<span class="highVAL">123</span>).toString()<br>(<span class="highVAL">100</span> + <span class="highVAL">23</span>).toString()</div>
<br>
<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_number_tostring" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<p>在 <a href="../jsref/jsref-obj-number.html">Number 方法</a> 章节中，你可以找到更多数字转换为字符串的方法：</p>
<table class="reference">
  <tbody><tr>
    <th style="width:25%">方法</th>
    <th>描述</th>
  </tr>
  <tr>
    <td>toExponential()</td>
    <td>把对象的值转换为指数计数法。</td>
  </tr>
	<tr>
    <td>toFixed()</td>
    <td>把数字转换为字符串，结果的小数点后有指定位数的数字。</td>
  </tr>
  <tr>
    <td>toPrecision()</td>
    <td>把数字格式化为指定的长度。</td>
  </tr>
</tbody></table>
<br>
<hr>

<h2>将布尔值转换为字符串</h2>

<p>全局方法 <strong>String()</strong> 可以将布尔值转换为字符串。 </p>

<div class="example">
<div class="example_code">
String(<span class="highVAL">false</span>)&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 "false"<br></span>
String(<span class="highVAL">true</span>)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp; <span class="highCOM">// 返回 "true"
</span></div>
</div>

<p>Boolean 方法 <strong>toString()</strong> 也有相同的效果。</p>

<div class="example">
<div class="example_code">
false.toString()&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 "false"<br></span>
true.toString()&nbsp; &nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 "true"
</span></div>
</div>
<br>
<hr>

<h2>将日期转换为字符串</h2>
<p>Date() 返回字符串。</p>
<div class="example">
<div class="example_code">
	Date()&nbsp;&nbsp;&nbsp; &nbsp; <span class="highCOM">// 返回 Thu Jul 17 2014 15:38:19 GMT+0200 (W. Europe Daylight Time)</span></div>
</div>
<p>
全局方法 String() 可以将日期对象转换为字符串。</p>
<div class="example">
<div class="example_code">
	String(new Date())&nbsp;&nbsp;&nbsp; &nbsp; <span class="highCOM">// 返回 Thu Jul 17 2014 15:38:19 GMT+0200 (W. Europe Daylight Time)</span></div>
</div>

<p> Date 方法 <strong>toString()</strong> 也有相同的效果。</p>

<div class="example">
<h2 class="example">实例</h2>
	<div class="example_code">obj = new Date()<br>
		obj.toString()&nbsp;&nbsp; <span class="highCOM">// 返回 Thu Jul 17 2014 15:38:19 GMT+0200 (W. Europe Daylight Time)</span></div>
</div>

<p>在 <a href="../jsref/jsref-obj-date.html">Date 方法</a> 章节中，你可以查看更多关于日期转换为字符串的函数：</p>
<table class="reference">
<tbody><tr>
<th>方法</th>
<th>描述</th>
</tr>
<tr>
<td>getDate()</td>
<td>从 Date 对象返回一个月中的某一天 (1 ~ 31)。</td>
</tr>
<tr>
<td>getDay()</td>
<td>从 Date 对象返回一周中的某一天 (0 ~ 6)。</td>
</tr>
<tr>
<td>getFullYear()</td>
<td>从 Date 对象以四位数字返回年份。</td>
</tr>
<tr>
<td>getHours()</td>
<td>返回 Date 对象的小时 (0 ~ 23)。</td>
</tr>
<tr>
<td>getMilliseconds()</td>
<td>返回 Date 对象的毫秒(0 ~ 999)。</td>
</tr>
<tr>
<td>getMinutes()</td>
<td>返回 Date 对象的分钟 (0 ~ 59)。</td>
</tr>
<tr>
<td>getMonth()</td>
<td>从 Date 对象返回月份 (0 ~ 11)。</td>
</tr>
<tr>
<td>getSeconds()</td>
<td>返回 Date 对象的秒数 (0 ~ 59)。</td>
</tr>
<tr>
<td>getTime()</td>
<td>返回 1970 年 1 月 1 日至今的毫秒数。</td>
</tr>
</tbody></table>
<br>

<hr>
<h2>将字符串转换为数字</h2>
<p>全局方法 <strong>Number()</strong> 可以将字符串转换为数字。</p>
<p>字符串包含数字(如 "3.14") 转换为数字 (如 3.14).</p>
<p>空字符串转换为 0。</p>
<p>其他的字符串会转换为 NaN (不是个数字)。</p>

<div class="example">
<div class="example_code">
Number(<span class="highVAL">"3.14"</span>)&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 3.14<br></span>
Number(<span class="highVAL">" "</span>)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 0 <br></span>
Number(<span class="highVAL">""</span>)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 	<span class="highCOM">// 返回 0<br></span>
Number(<span class="highVAL">"99 88"</span>)&nbsp;&nbsp; <span class="highCOM">// 返回 NaN
</span></div>
</div>
<p>在 <a href="../jsref/jsref-obj-number.html">Number 方法</a> 章节中，你可以查看到更多关于字符串转为数字的方法：</p>
<table class="reference">
  <tbody><tr>
    <th style="width:25%">方法</th>
    <th>描述</th>
  </tr>
  <tr>
    <td>parseFloat()</td>
    <td>解析一个字符串，并返回一个浮点数。</td>
    </tr>
  <tr>
    <td>parseInt()</td>
    <td>解析一个字符串，并返回一个整数。</td>
    </tr>
</tbody></table>
<br>

<hr>

<h2>一元运算符 + </h2>

<p> <strong>Operator + </strong> 可用于将变量转换为数字：</p>
<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highELE">var</span> y = <span class="highVAL">"5"</span>;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<span class="highCOM">// y 是一个字符串<br></span>
<span class="highELE">var</span> x = + y;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
<span class="highCOM">// x 是一个数字
</span></div>
<br>
<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_typeof3" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<p>如果变量不能转换，它仍然会是一个数字，但值为 NaN 
(不是一个数字):</p>
<div class="example">
<h2 class="example">实例</h2>
<div class="example_code">
<span class="highELE">var</span> y = <span class="highVAL">"John"</span>;&nbsp;&nbsp;
<span class="highCOM">// y 是一个字符串<br></span>
<span class="highELE">var</span> x = + y;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="highCOM">// x 是一个数字 (NaN)</span></div>
<br>
	<a class="tryitbtn" href="../try/tryit.php?filename=tryjs_typeof4" target="_blank" rel="noopener noreferrer">尝试一下 »</a>
</div>
<br>

<hr>
<h2>将布尔值转换为数字</h2>
<p>全局方法 <strong>Number()</strong> 可将布尔值转换为数字。</p>

<div class="example">
<div class="example_code">
Number(<span class="highVAL">false</span>)&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 0<br></span>
Number(<span class="highVAL">true</span>)&nbsp; &nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 1
</span></div>
</div>
<br>
<hr>

<h2>将日期转换为数字</h2>

<p>全局方法 <strong>Number()</strong> 可将日期转换为数字。</p>

<div class="example">
<div class="example_code">
d = <span class="highELE">new</span> Date();<br>Number(d)&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 1404568027739
</span></div>
</div>


<p>日期方法 <strong>getTime()</strong>   也有相同的效果。</p>

<div class="example">
<div class="example_code">
d = <span class="highELE">new</span> Date();<br>d.getTime()&nbsp;&nbsp;&nbsp; &nbsp; &nbsp; <span class="highCOM">// 返回 1404568027739
</span></div>
</div>
<br>

<hr>

<h2>自动转换类型</h2>
<p>当 JavaScript 尝试操作一个 "错误" 的数据类型时，会自动转换为 "正确" 的数据类型。</p>
<p>以下输出结果不是你所期望的：</p>

<div class="example">
<div class="example_code">
	<span class="highVAL">5</span> + <span class="highVAL">null</span>&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 null 转换为 0<br></span><span class="highVAL">"5"</span> + <span class="highVAL">null</span>&nbsp; <span class="highCOM">// 返回"5null"&nbsp;&nbsp; 
	 null 转换为 "null"<br></span>
	<span class="highVAL">"5"</span> + <span class="highVAL">1</span> &nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 "51"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 1 转换为 "1"&nbsp; <br></span>
	<span class="highVAL">"5"</span> - <span class="highVAL">1</span>&nbsp;&nbsp;&nbsp;&nbsp; <span class="highCOM">// 返回 4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 "5" 转换为 5</span></div>
</div>
<br>

<hr>

<h2>自动转换为字符串</h2>
<p>当你尝试输出一个对象或一个变量时 JavaScript 会自动调用变量的 toString() 方法：</p>

<div class="example">
<div class="example_code">
document.getElementById(<span class="highVAL">"demo"</span>).innerHTML = myVar;<br><br>
<span class="highCOM">myVar = {name:"Fjohn"}&nbsp; // toString 转换为 "[object Object]"<br></span>
<span class="highCOM">myVar = [1,2,3,4]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // toString 转换为 "1,2,3,4"<br></span>
<span class="highCOM">myVar = new Date()&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // toString 转换为 "Fri Jul 18 2014 09:08:55 GMT+0200"<br></span>
</div>
</div>

<p>数字和布尔值也经常相互转换：</p>

<div class="example">
	<div class="example_code">
<span class="highCOM">myVar = 123&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // toString 转换为 "123"<br></span>
<span class="highCOM">myVar = true &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // toString 转换为 "true"<br></span>
<span class="highCOM">myVar = false&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // toString 转换为 "false"
</span></div>
</div>
 <p>下表展示了使用不同的数值转换为数字(Number), 字符串(String), 布尔值(Boolean):</p>
<table class="reference">
 <tbody><tr>
  <th>原始值</th>
  <th>转换为数字</th>
  <th>转换为字符串</th>
  <th>转换为布尔值</th>
  <th>实例</th>
 </tr>
 <tr>
  <td>false</td>
  <td>0</td>
  <td>"false"</td>
  <td>false</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_false" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>true</td>
  <td>1</td>
  <td>"true"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_true" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>0</td>
  <td>0</td>
  <td>"0"</td>
  <td>false</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_number_0" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>1</td>
  <td>1</td>
  <td>"1"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_number_1" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>"0"</td>
  <td>0</td>
  <td>"0"</td>
  <td class="important">true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_0" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>"000"</td>
  <td>0</td>
  <td>"000"</td>
  <td class="important">true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_000" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>"1"</td>
  <td>1</td>
  <td>"1"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_1" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>NaN</td>
  <td>NaN</td>
  <td>"NaN"</td>
  <td>false</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_nan" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>Infinity</td>
  <td>Infinity</td>
  <td>"Infinity"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_infinity" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>-Infinity</td>
  <td>-Infinity</td>
  <td>"-Infinity"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_infinity_minus" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>""</td>
  <td class="important">0</td>
  <td>""</td>
  <td class="important">false</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_empty" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>"20"</td>
  <td>20</td>
  <td>"20"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_number" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>"Runoob"</td>
  <td>NaN</td>
  <td>"Runoob"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_string_text" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>[ ]</td>
  <td class="important">0</td>
  <td>""</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_array_empty" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>[20]</td>
  <td class="important">20</td>
  <td>"20"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_array_one_number" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>[10,20]</td>
  <td>NaN</td>
  <td>"10,20"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_array_two_numbers" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>["Runoob"]</td>
  <td>NaN</td>
  <td>"Runoob"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_array_one_string" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>["Runoob","Google"]</td>
  <td>NaN</td>
  <td>"Runoob,Google"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_array_two_strings" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>function(){}</td>
  <td>NaN</td>
  <td>"function(){}"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_function" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>{ }</td>
  <td>NaN</td>
  <td>"[object Object]"</td>
  <td>true</td>
  <td><a class="tryitbtn" href="../try/try.php?filename=tryjs_type_convert_object" target="_blank" rel="noopener noreferrer">尝试一下 »</a></td>
 </tr>
 <tr>
  <td>null</td>
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		<li class="comment even thread-even depth-1" id="comment-20452"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;夜尽</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;972***483@qq.com</p></div><div id="runoobvote-id-20452" data-commid = "20452" class="upvotejs"><a class="upvote"></a> <span class="count">79</span></div></div><div class="comt-main" id="div-comment-20452"><h2>检测数据类型：typeof 与 instanceof</h2>
<p><strong>typeof</strong></p>
<p>typeof 用以获取一个变量或者表达式的类型，typeof 一般只能返回如下几个结果：</p>

<pre>number,boolean,string,function（函数）,object（NULL,数组，对象）,undefined。</pre>
<p>实例：</p>

<pre>document.getElementById("demo").innerHTML = 
typeof "john" + "&lt;br&gt;" + 
typeof 3.14 + "&lt;br&gt;" +
typeof false + "&lt;br&gt;" +
typeof [1,2,3,4] + "&lt;br&gt;" +
typeof {name:'john', age:34};</pre>
<p><a class="tryitbtn" href="https://c.runoob.com/codedemo/96" target="_blank" rel="nofollow">尝试一下 »</a></p>
 

<p>我们可以使用 typeof 来获取一个变量是否存在，如 <span class="marked">if(typeof a!="undefined"){}</span>，而不要去使用 if(a) 因为如果 a 不存在（未声明）则会出错。</p>

 

<p>正因为 typeof 遇到 null,数组,对象时都会返回 object 类型，所以当我们要判断一个对象是否是数组时。</p>

<p>或者判断某个变量是否是某个对象的实例则要选择使用另一个关键语法 <strong>instanceof</strong></p>。

<p><strong>instanceof</strong></p>
<p>可通过 instanceof 操作符来判断对象的具体类型，语法格式:</p>
<pre>var result = objectName instanceof objectType</pre>
<p>返回布尔值，如果是指定类型返回 true，否则返回 false：</p>
<p>例：</p><pre>
arr = [1,2,3];
if(arr instanceof Array){
    document.write("arr 是一个数组");
} else {
    document.write("arr 不是一个数组");
}
</pre>
<p><a class="tryitbtn" href="https://c.runoob.com/codedemo/4505" target="_blank" rel="nofollow">尝试一下 »</a></p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">夜尽</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;夜尽</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;972***483@qq.com</p></div></span>6年前 (2017-11-16)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-34022"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Endl</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;313***2538@qq.com</p></div><div id="runoobvote-id-34022" data-commid = "34022" class="upvotejs"><a class="upvote"></a> <span class="count">39</span></div></div><div class="comt-main" id="div-comment-34022"><p><strong>undefined 与 null 的区别：</strong></p>

<p>表面上 undefined 与 null 都是什么都没有的意思，但是实际上 undefined 是未定义（就是变量没有初始化），null 是一个变量初始化了，但是什么值都没给，只给了一个空对象；进一步说，undefined 与 null是值相等，类型不相等。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Endl</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Endl</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;313***2538@qq.com</p></div></span>5年前 (2018-08-14)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-39490"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Arcy</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;hen***55@163.com</p></div><div id="runoobvote-id-39490" data-commid = "39490" class="upvotejs"><a class="upvote"></a> <span class="count">45</span></div></div><div class="comt-main" id="div-comment-39490"><p>NaN 是一个特殊的数值，NaN 即非数值（Not a Number），这个数值用于本来要返回数值的操作数未返回数值的情况。</p>

<p>NaN 与任何值都不相等，包括 NaN 本身。</p>

<p>可以通过 isNaN() 方法来判断某个数值是否是NaN这个特殊的数，使用 isNaN() 方法会将传入的数值如果是非数值的会将其自动转换成数值类型，若能转换成数值类型，那么这个函数返回 false，若不能转换成数值类型，则这个数就是 NaN，即返回 true。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Arcy</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Arcy</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;hen***55@163.com</p></div></span>4年前 (2019-01-31)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-49133"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;渐漠</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;763***666@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://zhidao.baidu.com/question/618374304848945692.html">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-49133" data-commid = "49133" class="upvotejs"><a class="upvote"></a> <span class="count">119</span></div></div><div class="comt-main" id="div-comment-49133"><p>判断是否为数组。</p>
<pre>&lt;p id="demo"&gt;&lt;/p&gt;
&lt;script&gt;
var fruits = ["Banana", "Orange", "Apple", "Mango"];
document.getElementById("demo").innerHTML = isArray(fruits);
function isArray(myArray) {
    return myArray.constructor.toString().indexOf("Array") &gt; -1;
}
&lt;/script&gt;</pre>
<p><strong data-title>return myArray.constructor.toString().indexOf("Array") &gt; -1;这句话怎么解释?</strong></p>
<p>1、myArray 是函数 isArray 的参数，这里调用函数的时候，会传来数组 fruits。</p>
2、constructor 是一个属性，构造函数属性，不同类型的数据，会得到相应不同的值。因为 myArray 是个数组，这里的 myArray.constructor 的值就是 <span class="marked">function Array() { [native code] }</span>。(如果 myArray 是个字符串，myArray.constructor 的值就是<span class="marked">function String() { [native code] }</span>。还有 number，boolean，object，等等。)
<p>3、toString() 是个方法，变字符串的方法，这里把 <span class="marked">function Array() { [native code] }</span> 变成字符串，为了后面好检索。</p>
<p>4、indexOf("Array") 是个方法，检索字符串，这里看字符串 <span class="marked">function Array() { [native code] }</span> 里有没有Array，有就返回首次出现的位置，是一个数值，这里是 9。如果出现在第一个字符，会返回 0。空格参与计数。如果没有找到，就返回 -1。只要 &gt;-1，就说明有 Array，就能判断原来那个函数调用传来的 fruits 是一个数组。如果 <span class="marked">myArray.constructor.toString().indexOf("Object")&gt;-1</span>，那么 myArray 就是一个 Object 对象。不过那样地话，这个参数的名字就没取好了，应该叫做 myObject。</p><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="../note/49133">渐漠</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;渐漠</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;763***666@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://zhidao.baidu.com/question/618374304848945692.html">&nbsp;&nbsp;参考地址</a></p></div></span>3年前 (2019-12-09)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-49552"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Kotori、Waifu</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;747***886@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://zhidao.baidu.com/question/472692282.html">&nbsp;&nbsp;参考地址</a></p></div><div id="runoobvote-id-49552" data-commid = "49552" class="upvotejs"><a class="upvote"></a> <span class="count">28</span></div></div><div class="comt-main" id="div-comment-49552"><p>字符串转日期：</p>

<pre>var str = "2019-12-25";
// 转换日期格式
str = str.replace(/-/g, '/'); // "2010/08/01";
// 创建日期对象
var date = new Date(str);
反之，日期类型转化为格式化的字符串：

//完整的格式化  
var time2 = new Date().format("yyyy-MM-dd hh:mm:ss");
Date.prototype.format = function (fmt) {
    var o = {
        "M+": this.getMonth() + 1,                 //月份 
        "d+": this.getDate(),                    //日 
        "h+": this.getHours(),                   //小时 
        "m+": this.getMinutes(),                 //分 
        "s+": this.getSeconds(),                 //秒 
        "q+": Math.floor((this.getMonth() + 3) / 3), //季度 
        "S": this.getMilliseconds()             //毫秒 
    };
    //处理年份
    var reYear = /(y+)/; 
    var resultYear = reYear.exec(fmt);
    if (resultYear) 
    {
        var yearformatPart = resultYear[0];//匹配到的格式化字符
        var yearVal = (this.getFullYear() + "").substr(4 - yearformatPart.length);
        fmt = fmt.replace(yearformatPart, yearVal);
    }
    for (var k in o) {
        var re = new RegExp("(" + k + ")");
        var re = re.exec(fmt);
        if (re) {
            var Val = "" + o[k];//本次需要替换的数据 
            var formatPart = re[0];//匹配到的格式化字符
            var replaceVal = (formatPart.length == 1) ? (Val) : (("00" + Val).substr(Val.length));
            fmt = fmt.replace(formatPart, replaceVal);
        }
    }
    return fmt;
}</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">Kotori、Waifu</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;Kotori、Waifu</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;747***886@qq.com</p><p><i class="fa fa-external-link" aria-hidden="true"></i> <a rel="nofollow" target="_blank" href="https://zhidao.baidu.com/question/472692282.html">&nbsp;&nbsp;参考地址</a></p></div></span>3年前 (2019-12-25)</div></div></li><!-- #comment-## -->
<li class="comment odd alt thread-odd thread-alt depth-1" id="comment-67109"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;衣冠</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;227***1235@qq.com</p></div><div id="runoobvote-id-67109" data-commid = "67109" class="upvotejs"><a class="upvote"></a> <span class="count">9</span></div></div><div class="comt-main" id="div-comment-67109"><p>补充一下，通常来讲，使用 instanceof 就是判断一个实例是否属于某种类型，更重要的是 instanceof 可以在继承关系中用来判断一个实例是否属于它的父类型。</p>
<p>
用 instanceof 来判断类型只能用于对象层面，不是一个对象则不行：</p>

<pre>str = "asd";
if(str instanceof String)//返回false
   document.write("YES");//不会打印YES
str = new String();
if(str instanceof String)//返回true
  document.write("yes");//不会打印yes</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">衣冠</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;衣冠</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;227***1235@qq.com</p></div></span>2年前 (2021-09-28)</div></div></li><!-- #comment-## -->
<li class="comment even thread-even depth-1" id="comment-70832"><span class="comt-f">#0</span><div class="comt-avatar wrapper"><i style="font-size:36px;" class="fa fa-user-circle" aria-hidden="true"></i><div class="tooltip"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;suika</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;137***0916@qq.com</p></div><div id="runoobvote-id-70832" data-commid = "70832" class="upvotejs"><a class="upvote"></a> <span class="count">6</span></div></div><div class="comt-main" id="div-comment-70832"><p><strong>NaN</strong> 这个特殊的数值也可以使用 <span class="marked">Object.is()</span> 方法来判断。</p>

<p>并且在这个方法中还可以判断 <strong>+0</strong> 和 <strong>-0</strong>。</p>

<pre>console.log(Object.is(NaN, NaN)); //true
console.log(Object.is(+0, -0)); //false
console.log(Object.is(+0, 0)); //true
console.log(Object.is(0, -0)); //false</pre><div class="comt-meta wrapper"><span class="comt-author"><a target="_blank" href="javascript:;">suika</a><div class="tooltip tooltip1"><p><i class="fa fa-user" aria-hidden="true"></i>&nbsp;&nbsp;&nbsp;suika</p><p><i class="fa fa-envelope" aria-hidden="true"></i>&nbsp;&nbsp;137***0916@qq.com</p></div></span>1年前 (2022-03-07)</div></div></li><!-- #comment-## -->
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		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});
	$("#user_add_note").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		$('html, body').animate({
       	    scrollTop: $("#respond").offset().top
    	}, 200);
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" style="display:none;" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  10989;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>').show();
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>').show();
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>').show();
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>').show();
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>').show();
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>').show();
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	$(".comt-author").click(function() {
		href = $(this).children("a").attr("href");
		if(href.indexOf("/note/")!=-1) {
			var win = window.open(href, '_blank');
  			win.focus();
		}
	});
	$(".comt-meta span").hover(function(){
		$(this).children(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).children(".tooltip").removeAttr("style");
	});
	/*
	$(".wrapper i").hover(function(){
		$(this).siblings(".tooltip").css({ "opacity": 1, "pointer-events": "auto"});
	},function(){
		$(this).siblings(".tooltip").css({ "opacity": 0, "pointer-events": "auto"});
	});
	*/
	//Upvote.create('runoobvote-id', {callback: vote_callback});
	var ajaxurl = 'https://www.runoob.com/wp-admin/admin-ajax.php';
	var callback = function(data) {
		//console.log($('#runoobvote-id').upvote('upvoted'));
		//console.log($('#runoobvote-id').upvote('downvoted'));
		//console.log(data);
		_vote_action = data.action;
		id_arr = data.id.split('-');
		um_id= id_arr[2];
		//console.log(um_id);
		
		var re = /^[1-9]+/;
		if (re.test(um_id)) { 
			var ajax_data = {
				_vote_action: _vote_action,
				action: "pinglun_zan",
				um_id: um_id,
				um_action: "ding"
			};
			//console.log(ajax_data);
			$.post(ajaxurl,ajax_data,function(status){
				//if(status.vote_num>999) {
				//	_voteHtml = '<span style="display: block; text-align: center;font-size: 20px; color: #6a737c; margin: 8px 0;">'+kFormatter(status.vote_num) +'</span>';
				//	$("#runoobvote-id-" + um_id + " .count").hide().after(_voteHtml);
				//}
				
			});
		}
	};
	if($('#comments').length && $('.upvotejs').length){
		$('.upvotejs').upvote({id: 10989, callback: callback});
	
		$.post(ajaxurl,{"action":"pinglun_zan","postid":10989},function(data){  
			$(data).each(function(key,value) {
				$("#runoobvote-id-" + value.commid + " .upvote").addClass(value.upvotejs_class);
				$("#runoobvote-id-" + value.commid + " .downvote").addClass(value.downvote_class);
				$("#runoobvote-id-" + value.commid + " .count").text(value.upvote_count);
			})
		},'json');
		
	}
	
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
function kFormatter(num) {
	// return num;
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}

</script>

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